Clinical trials of Chinese vaccine similar to Ebola immunizer in Canada to begin in weeks

The first human clinical trials in Canada for a vaccine to COVID-19 should be underway in the country within weeks, which – if the candidate proves successful – could start a process as short as several months long toward readying the product for Canadian production.

Prime Minister Justin Trudeau’s weekend announcement that Health Canada had approved a leading vaccinology lab to begin human testing for a COVID-19 vaccine produced by CanSino came less than a week after the National Research Council shared news of its partnership with the Chinese vaccine-maker.

The Canadian Centre for Vaccinology (CCfV), which operates out of Dalhousie University, is now awaiting only the green light from its research ethics board before it can launch into the first phase of its trials, centre director Dr. Scott Halperin said. Halperin’s “hope” is that its clinical trials will be approved “within the next week or two.”

Clinical trials

Halperin said CCfV’s study is what’s called a “Phase 1-2” study, making two typically separate stages of a study more concurrent.

Phase 1 will include introducing CanSino’s vaccine candidate to somewhere between 30 and 100 healthy people between the ages of 18 and 55.

“(The) main objective is safety and tolerability of the vaccine while getting an early look at the immune response,” Halperin said.

Vaccine development usually can take years and CCfV will be monitoring the participants of its trial for six to eight months, according to Halperin.

The CCfV director said the earliest a Phase 3 study, which would include thousands of people taking the vaccine candidate, could begin would be early fall.

“Phase 3 studies are studying not only is it safe, not only does it have a good immune response, but does it protect people if they’re exposed to the infection as they’re wandering around in their daily lives?” Halperin said.

Because of the widespread impact of the COVID-19 pandemic, however, Halperin suggested Health Canada could be influenced into approving the vaccine if the early trials show promise, much as it did for the H1N1 pandemic vaccine.

The agreement between CanSino and NRC that now involves CCfV will allow NRC access to the vaccine technology, which will allow it to manufacture it in Canada.

“That would guarantee us, if this vaccine is successful, a supply of the vaccine for Canadians,” Halperin said.

CanSino’s vaccine that CCfV is testing is called Ad5-nCoV, standing for the Recombinant Novel Coronavirus Disease Vaccine, and has been one of the fastest-progressing vaccine candidates for COVID-19 in the world.

The Ad5-nCoV was also created by CanSino in a similar way as it produced its Ebola vaccine, which was called Ad5-EBOV.

Ad5-nCoV is a genetically modified adenovirus, which are different viruses from coronaviruses. Pink eye is one of the most well-known illnesses caused by adenoviruses. Like the new coronavirus, SARS-CoV-2, which causes COVID-19, the virus the vaccine is based off of, adenovirus type-5, is a respiratory virus. Adenovirus type-5 doesn’t normally cause many symptoms.

Ad5-nCoV makes for an enticing vaccine candidate because the adenovirus it’s based on can’t replicate in humans, meaning that people can be injected with its vector (its weakened vaccine-form) without fear of getting sick from the adenovirus. CanSino were able to further modify the virus to carry one of the key characteristics specific to SARS-CoV-2 – its spike protein.

SARS-CoV-2 uses spike proteins to penetrate cells and attach itself, helping it spread. The spike proteins carried by the new coronavirus are thought of as important targets for vaccines because if they’re neutralized the disease has a harder time spreading from cell-to-cell.

Because the new coronavirus’ spike proteins are replicated in Ad5-nCoV, when someone is given the adenovirus vector their immune system can start producing antibodies to SARS-CoV-2 without ever coming into contact with the virus.

Halperin also explained that the vaccine triggers the response of T cells, which have various abilities, including the capability of killing virus-infected cells and producing signalling proteins that help other cells curb virus replication.

CCfV is one of 10 sites across Canada that has capacity to conduct human clinical trials for vaccines like Ad5-nCoV, according to Halperin.

The director of VIDO-InterVac, which has produced one of the furthest-along made-in-Canada vaccines, told iPolitics less than two week ago that he had been in discussions with CCfV about co-ordinating large-scale testing for its immunizer. VIDO-InterVac is linked to the University of Saskatchewan and has reported promising preliminary results in the trials that it’s conducted on animals.

“You’ll be seeing over the next couple of months ‘Phase I’ studies being done at multiple sites across our network,” said Halperin, who is also the leading researcher of CIRN.